Trim member



United States Patent TRIM MEMBER David M. Gustafson, Garden Grove, Calif., assignor to Angeles Metal Trim (30., Los Angeles, Calif., a corporation of California Filed June 18, 1957, Ser. No. 666,302

2 Claims. c1. 50-165) This invention relates to improvements in building construction and more particularly to an improved trim member for use in combination dry-wall and plaster conconstruction.

In applying dry-wall construction to homes and other buildings, the walls are formed by means of wallboard, such as gypsum-rock panels, having cardboard or similar sheets on the outer surfaces thereof. Where the edge of a piece of wallboard lies at a corner of a wall structure, such as at the corner formed along the edge of a door, window, or other opening, it is desirable to make some provision for protecting and concealing the edge of the wallboard. Numerous types of trim members, principally metal, have been devised and employed for this purpose. One type of trim member, now standard, is provided with a bead to form a rigid orthogonal corner which protects and conceals the raw edge of the wallboard but is ineffective to properly join a wallboard and plaster wall type of construction, as will be explained more fully hereinafter. The bead is provided to strengthen the trim member, as the sections of the trim member secured to the wall forming members are usually made of the thinnest material possible, and also for purposes of applying a joint cement over that portion of the trim member lying adjacent to the wallboard. This joint cement is spread from the bead, over and beyond the edge of the trim member onto the wallboard surface. Thus, the joint cement not only covers the trim member and its means of attachment to the wallboard, but serves to provide a monolithic structure which will accept paint or other such covering materials.

In certain localities, the use of wallboard in recesses around bath tabs and shower stalls is prohibited. The wall construction in such recesses is frequently of lathand-plaster or of button-board plaster lath covered with an overlay of plaster. Where the corners occur between the junction of the wallboard and the plaster, great difficulties have been experienced in effecting a satisfactory juncture which would not only protect and conceal the edge of the wallboard but would also form a satisfactory key to the plaster adjoining the end of the wallboard and would also enable such juncture to afford a pleasing appearance. Various attempts to meet this problem have been made with the various types of standard trim members now on the market. Little success has been had with such makeshift arrangements.

It is an object of my invention, therefore, to provide an improved trim member which can be used successfully at the juncture of wallboard and plaster wall construction.

Another object of my invention is to provide an improved trim member that is relatively inexpensive to manufacture and apply and that forms a strong juncture between a combination dry-wall and plaster wall construction.

A further object of my invention is to provide an improved trim member which provides a key for locking a Patented Jan. 31, 1961 plaster wall construction at the corner juncture between the plaster wall and a wallboard.

Another object of my invention is to provide an improved trim member for use at the corner juncture between a dry-wall and a plaster wall which will allow the formation of a corner construction that is pleasing to the eye.

The foregoing and other objects of the invention, together with the various advantages thereof, will become apparent from the following description taken in conjunction with the accompanying drawing wherein like reference characters denote like parts throughout the several views, and wherein:

Fig. 1 is a cross-sectional view of a corner construction utilizing prior art standard trim members;

Fig. 2 is a cross-sectional view of a similar corner construction embodying my invention; and

Fig. 3 is a perspective view of my improved trim member as employed in Fig. 2.

Referring to the drawing, and particularly to Fig. 1, there is illustrated a portion of a corner construction at the junction of a wallboard and plaster wall. The wallboard 10 is erected against the side 11 of the structural or framing member 12. Wood lath or button plasterboard lath 14 is then secured to the side 15 of the tram-- ing member 12. These laths are usually nailed or otherwise fastened in place against the framing members, the fastening members not being shown. A right-angled trim member 16 having a corner bead 18 is then laid up against the end of the wallboard 10 and fastened in place by the nails 20 which pass through the trim member and wallboard into the framing member. As will be noted, the trim member is placed so as to extend beyond the end of the wallboard, framing member and lath so as to leave a space 22 for the reception of the plaster 24.

The plaster 24 is then applied to the lathing. Great care must be taken to fill space 22 with plaster in order to make a proper corner juncture and to fully support the portion of the trim 16 overlying the plaster wall. After completion of the plastering and upon the setting of the plaster, nails 26 are driven through the trim member, plaster and lath into the framing member 10. Before the plaster is completely dry, the surfaces of the trim member are covered with bodies of joint cement 28a and 28b. Instead of using joint cement at 28b, some builders cover the portion of the trim member adjacent the plaster wall with a thin wash of plaster so as to give .an even texture to the finished plaster wall up to the bead 18.

The great disadvantages in this type of construction, as shown in Fig. l, are obvious. It has been found very ditlicult to work the plaster properly into the space 22 so as to provide a properly keyed and strengthened joint. Also, the driving of nails 26 through the plaster generally results in cracking the plaster. If the nails are driven before the plaster is applied, the trim is bent, resulting in an unsightly juncture, and the difiiculties of working the plaster into the space 22 are enhanced. Further, the use of joint cement at 28b, being of a different material, renders the finishing difiicult due to the difference in texture between the cement and the plaster. If a plaster wash is used instead of the joint cement, very poor adhesion between the plaster and the material used in the trim member generally results and the thin plaster coating is almost certain to crack or separate in patches, leaving an unsightly corner.

In order to obviate the above disadvantages, my invention contemplates an improved trim member so dis posed as to lockingly engage with the plaster wall whereby the raw edge of the connecting wallboard is protected and concealed and the plaster wall is firmly secured at the juncture of the two walls,

With reference to Fig. 2, the vertical structural or framing member 12 defines one corner between the wallboard wall 10 and the plaster wall 24- where the plaster wall leads into a bath recess. This vertical framing member may be secured to the ceiling framing (not shown). Another similar framing member may be used at the other end of the recess or, as is usual, the end wall of the recess is continuous with the whole end wall of the room. In the latter event, it is customary to use lath and plaster for the whole end wall.

A panel or other piece of wallboard 1% is placed against the outboard side 11 of framing member 12 with its raw edge approximately flush with the recess side 15 of the framing member. A strip of my improved trim member 30, usually 8 feet 2 inches in length, is placed on the wallboard, overhanging the edge of framing memher face 15 and the edge of the wallboard about of an inch with the keying projection 36 extending inwardly into the recess 35 or otherwise toward the framing member 12. Fastening nails 32 are then driven through the trim member and wallboard into the framing member, securely holding the trim member and wallboard in place. Lath or button-board plaster lath 14 has been previously fastened in place with suitable fasteners (not shown. Plaster is then applied over the lath or plaster board lath, filling the space 35 behind the keying projection 36. Plaster is then smoothed over the keying projection 36 and the rest of the wall until it is of uniform depth and is flush with the outer edge of convex bead 34. It is to be understood that several coats of plaster may be applied, i.e., first rough or scratch coat; second brown coat; and third finish coat.

It can thus be seen that by the use of my improved trim member, the raw edge of the wallboard is concealed and protected and the required plaster wall is strongly keyed thereto without the need of fastening devices holding the plaster directly to the framing member. A smoothly textured plaster wall is thus provided right up to the corner defined by the outer edge of the convex, that is the outwardly projecting or extending bead, 341. In finishing off the corner, the reentrant portion, formed between the outer edge of the convex bead 34 and the sides of the wallboard adjacent to and beyond the edge 42 of the trim member section 46, is filled with bodies 44 of suitable filler material, such as joint cement; the forwardly projecting convex head 34 forming a boundary for the bodies of filler. Several coats of filler material are applied until the outer surface thus provided is flush with the outer edge of bead 34.

The improved trim member 30, which may be con-' structed by bending, rolling, or extruding a thin strip of metal, plastic, or other suitable material, thus comprises a front trim member section 4% having an edge 52 and a forwardly projecting convex bead 34. Edge 42 and bead 34 are parallel to each other. Bead 34 may project forwardly from the plane of section 40 between and of an inch. Bead 34- is slanted away from the plane of the section 463 so as to form an obtuse angle of approximately 150. While the value of this angle is not critical, it should be sufficiently obtuse as to provide easy fairing of the joint cement, or other suitable material, coated over the section 46 and adjacent wallboard and yet be of such a value as to create a reentrarzt portion deep enough to allow the joint cement to adhere well to the bead 34 and provide sufficient material to facilitate feathering the joint cement on the outer sur face of the bead.

The other side of the head 34 is carried around to form the plaster keying projection 36. This keying projection 36 is disposed at an acute angle with the plane of the front section 4-8 of approximately 60. Again, the value of this angle is not critical and may well vary between 80 and 45. The only criterion here would be to have a sufficient angle between the outer side 0f keying projection 36 and the surface of the plaster wall so as to provide a sufficient depth of plaster to adhere well to the outer surface of projection 36 and to be feathered against the outer edge of bead 34.

As shown in Fig. 3, front trim section 40 may be supplied with staggered rows of nailing apertures or holes 52, one row approximately central to the section and the other row close to the edge 42. These holes are placed approximately on 3-inch centers. Instead of the row of nailing holes along the edge 42, notches 54 are provided in an alternative embodiment of the invention for nailing or fastening purposes. Keying projection 36 is also provided with a row of bonding holes 56 in order to improve the adherence of the plaster thereto.

in another alternative embodiment of the invention, bonding holes 60 are provided in the front trim section 4% in order to improve the adherence of the bodies of joint cement 44 thereto. These bonding holes 60 are staggered with relation to the central row of holes 52 so as not to unnecessarily weaken the front trim section 40 and the trim member 30 as a whole.

In a practical form of my invention which is finding wide and ready acceptance in the building trade, my improved trim member is formed from a 2-inch strip of 26 gauge electro-galvanized steel. Upon completion of the forming operation, the overall width of the front trim section from the outer edge of bead 34 to the parallel edge 42 is approximately 1.76 inches. The head 34 extends forwardly .040 inches and the keying projection 36 extends rearwardly at an angle of 60 for a length of approximately .25 inches. These trim members are generally furnished in lengths of 8 feet 2 inches, as previously noted. Of course, other lengths could be supplied, dependent upon the requirements of the builder. While the trim member may be painted with a suitable undercoat base, such as zinc chromate, to facilitate the bonding of the joint cement and the plaster thereto, it has been found, for instance, that the electro-galvanized steel now being used does not require such undercoating.

While the invention has been described with particular reference to a specific embodiment thereof, it will now be obvious to those skilled in the art that many changes may be made in the shape and dimensions of the parts, in the materials of which the trim member is made, and in the methods and manner of producing and applying it without departing from the invention. While a specific example of a successful trim member has been described, there is no intention of being limited thereto as my invention contemplates other and further embodiments within the scope of the appended claims.

I claim:

1. In combination dry and plaster wall construction:

a structural framing member defining the exterior corner of a wall structure;

a panel of wallboard overlying said structural member;

an elongated trim member adapted to be placed along the edge of said wallboard panel at said structural member,

said elongated trim member having an elongated flat trim section with parallel elongated edges serving as a front trim section, an elongated flat trim section having elongated parallel edegs disposed at an acute angle with relation to the inner surface of said front trim section and serving as a plaster keying projection, and an elongated corner bead integrally joining the juxtaposed edges of said front trim section and said keying projection, said corner bead being disposed at an obtuse angle with relation to the outer surface of said front trim section;

fastener means for securing said trim member and wall board to said framing member, with the corner bead and keying projection of said trim member extending substantially beyond the edge of said wallboard and with said keying projection extending inwardly from the plane of the front of said wallboard toward said structural memher and terminating in spaced relation to said structural member; and

a plaster wall having a plane meeting the plane of said wallboard at an angle and covering said framing member, the edge of said wallboard, and the keying pro- 5 jection of said trim member and extending behind said projection, the plaster of said wall enclosing said keying projection and extending through the space between said structural member and the termination of said keying projection substantially into contact with the inner surface of said front trim section, said plaster being installed flush with the outer edge of said corner bead whereby the edges of said wallboard and said plaster wall are concealed and protected.

2. A combination dry and plaster wall corner construction as claimed in claim 1 wherein said flat front trim section is provided with two rows of apertures for inserting said fastener means and wherein said trim member plaster keying projection is provided with bonding holes for bonding said plaster thereto.

References Cited in the file of this patent UNITED STATES PATENTS 290,750 Da Cuna Dec. 25, 1883 10 2,041,799 Walper May 26, 1936 2,064,704 Vass Dec. 15, 1936 2,311,345 Mitchell Feb. 16, 1943 2,643,423 Brendel June 30, 1953 FOREIGN PATENTS 16,056 Great Britain July 6, 1897 

